Accelerometer‐measured physical activity and postmenopausal breast cancer incidence in the Women's Health Accelerometry Collaboration

Abstract

Background: Few studies have examined accelerometer-measured physical activity and incident breast cancer (BC). Thus, this study examined associations between accelerometer-measured vector magnitude counts per 15 seconds (VM/15s) and average daily minutes of light physical activity (LPA), moderate-to-vigorous PA (MVPA), and total PA (TPA) and BC risk among women in the Women's Health Accelerometry Collaboration (WHAC). Methods: The WHAC comprised 21,089 postmenopausal women (15,375 from the Women's Health Study [WHS]; 5714 from the Women's Health Initiative Objective Physical Activity and Cardiovascular Health Study [OPACH]). Women wore an ActiGraph GT3X+ on the hip for ≥4 days and were followed for 7.4 average years to identify physician-adjudicated in situ (n = 94) or invasive (n = 546) BCs. Multivariable stratified Cox regression estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for tertiles of physical activity measures in association with incident The last two authors contributed equally to this article.

Amount and intensity of physical activity and risk of incident cancer in the UK Biobank

“…28,32 Our findings align with other studies using accelerometer data that found physical activity may play a role in the prevention of PA-related cancers among older women 33 and for incident breast cancer. 15,16 In addition to finding lower risk for 7 of the 13 PA-related cancers identified by Moore and colleagues, 17 we also observed a protective association between total PA and non-Hodgkin lymphoma and suggestive associations for melanoma and pancreatic cancers.…”

“…Existing accelerometer-measured activity studies in cancer have primarily focused on cancer mortality and, 10–14 to a limited extent, breast cancer risk. 15,16…”

“…Existing accelerometermeasured activity studies in cancer have primarily focused on cancer mortality and, [10][11][12][13][14] to a limited extent, breast cancer risk. 15,16 To address these gaps and challenges, we aimed to understand the relationship between total daily activity and intensity, step counts, and incident cancer risk using a composite outcome of 13 cancer sites previously associated with low PA in studies of self-reported leisure time activity. 17 As a secondary analysis, we assessed the risks for all 13 PA-related cancers individually and, as case numbers allowed, for other site-specific cancers.…”